Some ascii reading optimization:

Here some measurments: gyrodata c&p to 8 million rows

Delimiters (comment, column) : time in readColumns
-----------------------------------------------------------
No comment, custom: one space : 1.69102 seconds
No comment, whitespace : 2.11194 seconds
default comment, custom: one space: 4.01525 seconds (default comment with 4 characters)
default comment, whitespace : 4.34039 seconds
default comment, custom ,;| : 6.49383 seconds (space at the end of 4 characters)